Best way to protect your iPhone Jet Black from scratches

Hello Guys,

Does anyone have any suggestion to protect your iPhone 7 Jet Black from scratches, I don't want to use a case I saw a company that do some kind of coating that stops the JB from getting scratched https://nanostate.co/jet-black-iphone-scratch-fingerprint-protector/ I can't find any reviews on it wonder if anyone else has experience with them? I'm also considering some kind of screen protector but I'm worried about buying a cheap flimsy one, any suggestions?